The purpose of this application is to solicit funding for a workshop on the use of nonmammalian species as early warning indicators of human health hazards in the environment. The current emphasis on the development of alternative technologies for human safety evaluations has focused significant attention on research concerning lower form organisms. This attention will inevitably provide toxicologists with sensitive tools for detecting environmental hazards. Various test systems are now identified in genetic toxicology, reproductive toxicology and neurotoxicology. The needs are to assess the current status of the concept of early warning indicators and to identify research goals in order to develop nonmammals as sentinels of environmental problems. These goals will be achieved by bringing together a forum of eminent environmental toxicologists in a workshop format. Toxicologists representing regulatory, genetic, reproductive, and neurological viewpoints will participate together in a platform session and separately in roundtable discussion to meet objectives for each area. The workshop will culminate in a floor discussion of the achievements made by the separate groups. A conference summary and review of accomplishments will be published in book form.